Speakers question (1 Viewer)

[Mike3783]

I'm in the market for a new home theatre system, and I'm just wondering what produces the watts. For example, if my current system is 400 watts (the reciever and speakers all came together in a box), and I want to buy something that produces 1200 watts, would I just have to buy a 1200 watt reciever and use the same speakers, or would I have to also buy new speakers?

Thanks

 

[ChrisWiggles]

I don't understand the point of your question.

But to address it: the amplifier is what produces the power to drive the speakers. It sound like you have a home theater in a box type setup. It is seriously unlikely it can actually produce 400 watts for anything more than an instant. Usually it does not take much power at all to get very loud just a fraction or a few watts for most speakers.

Obviously increasing the amplifier capabilities increases the power capabilities of the system which is a good thing in terms of headroom. One can certainly have more power capabilities than one needs and this is ok. Obviously if you turn it up too loud you can overdrive the speakers, but having an overpowered amplifier for the task is better than having an underpowered amp that you drive into clipping which is much more likely to damage the speakers than overpowering them.

A 1200 watt receiver, well I don't know of any receiver that would come anywhere NEAR that kind of power. Giant monoblocks would have difficulty even achieving that.

In any case, the greatest impact on the sound quality is the room and the speakers, so that's where the greatest improvements usually come from. You'd only need more power if the current amplifier is inadequate for the system and the task.

 

[Mike3783]

Thanks for the information ChrisWiggles.

 

[Bob McElfresh]

Power in a receiver is actually a complex topic. (Most of the time your receiver is putting out 5-10 watts). Manufacturers can exagerate the power, but not be called liars because they have fine-print somewhere.

Example: I have a very good HT receiver that made the "Best Equipment" list for several years, but it is only 80 watts. The devil is in the details. This number includes:

- 8 ohm speakers (not 6 or 4 that make numbers look better)
- All speakers driven 5 x 80 = 400 watts (some mfgs print the Stereo/2-channel numbers in large letters).
- Full range frequencies - higher frequencies take less power
- RMS power instead of peak or peak-to-peak or peak-envelope power which looks more impressive.

If you read the fine-print on your Home Theater in a Box - you will see how they made the system sound more powerful than it really is.

The other part of the deal is the speakers.

I keep an eye on local websites for used speakers/electronics and I chuckle every time I see someone trying to sell some huge, old speakers and claim they are "..powerfull 500 watt" speakers. Think about it - this means these speakers often need TONS of power to wake up and make noise. It is more truthfull to say "power-sucking" and "inefficient" for something like these.

Mike: can I give you some un-asked for advice?

A home-theater is NOT your fathers 70's era stereo where 2 huge speakers tried to sound like a concert hall ... in the next room.

A home-theater system surrounds a small area (1-3 seats) with a circle of speakers. You dont want it too-loud and you dont care how it sounds in the next room.

What you DO want is impressive BASS. This usually comes from a good subwoofer placed in the optimal position in the room. And this position is never where you put your L/R/Center speaker. The subwoofer is usually the big power-drain so they are often self-powered.

This is why a 80 watt-per-channel receiver with monitor-style speakers and a good sub can produce an outstanding HT experience. There are even some HTB's (Home Theaters in a Box) that do a fantastic job. (I have installed these for friends).

Dont be swayed by marketing terms that display large power numbers. This is to seduce the ignorant. Spend some time in the "Receivers" and "Speakers" fourm and you will start to see that good equipment does not usually come with huge power numbers.

Hope this helps.

 

[richn41]

Bob,

I saw your comment on the subwoofer position. I never really thought about this. Where would you recommend placing the sub?

 

[Jgoal55]

same question here. I was always told or at least I always thought that the placement of the subwoofer was not important. In other words, that a subwoofer can go anywhere in a room. Guess thats not right?

 

[Jeff Gatie]

Both answers are correct, but for different reasons. A sub will not be "localized" because sounds below ~80Hz are not able to be localized by the human ear. So you can place the sub anywhere in the room and your ear cannot tell where it is, unlike your other speakers which have to be placed in specific spots and aimed in specific ways to get the right directional effects. However, because of room reflections, the incorrect placement of a sub can cause peaks and nulls due to the long wavelenghts of sub-bass soundwaves interacting with their own reflections off the walls and ceilings. So the short answer is you can place the sub anywhere, but it may not sound as good in some spots vs. others in your particular room.

 

[Mike3783]

Thanks for the information guys, I appreciate it.

 

[Bob McElfresh]

Generally - the sub is placed in a corner of the 2 longest un-broken walls to give the maximum length of the 2 walls the ability to reflect the wavelengths.

But to an audiophile - this over-emphasis of some sounds is not good.

One technique is this:

Equipment: 6 pack of favorite beer, Long RCA cable (CATV coax with "F-to-RCA-Male" adaptors work fine.

First: place the sub in the primary seating location
Second: Disconnect the other speakers
Third: Play a bass-heavy track
Fourth: Go to the corner of the room and slowly crawl along the longer wall and listen to the sound. You will find spots where the sound is boomy/rough, and other spots where the sound is smooth & tight. Put a bottle of beer at the good locations.

You should have 2-5 places marked with beer. Re-locate the sub in the one of the spots, put your chair back, reconnect the speakers and listen while drinking the beer. If the sound is not pleasing, put the sub in the second-best location and drink that beer.

Eventually you will have found the best spot for your sub, or be so drunk you wont care anymore.

Hope this helps.